1. Field of the Invention
The present invention relates to a method of treating the surface of a semiconductor substrate.
2. Related Art
In the process of manufacturing a semiconductor device, there is performed a treatment for supplying a treatment solution (chemical solution or pure water) to the surface of a semiconductor wafer as a substrate to be treated. In particular, in a cleaning treatment of a semiconductor wafer, a chemical solution for the cleaning treatment is supplied to the surface of the wafer, and thereafter a rinse treatment is performed by supplying pure water to the surface of the wafer. After the rinse treatment, there is performed a drying treatment for removing the pure water left on the wafer surface and for drying the wafer. As a method for performing the drying treatment, there is, for example, a method of drying the wafer in such a manner that IPA (Isopropyl alcohol) is used to substitute the pure water on the wafer with IPA.
However, there is a problem that a pattern formed on the wafer is collapsed by the surface tension of the solution during the drying treatment. In order to solve the problem, there are proposed a method of using a solution with low surface tension, such as HFE (hydrofluoroether) instead of IPA, and a method of using a supercritical process.
However, according to miniaturization of pattern dimensions in recent years, it has become difficult to prevent the pattern collapse even by using HFE. Further, even in the supercritical process, it is known that the pattern collapse is caused when moisture, or the like, is brought into a chamber in which a supercritical atmosphere is realized.